System and method for pedicle screw placement in vertebra

ABSTRACT

Disclosed herein are device and methods for determining an orientation of an instrument for inserting a medical device in a bone. One such method includes simulating an insertion point and an orientation of a simulated surgical hardware installation on a diagnostic representation of the bone, and then using an electronic device to align an instrument for inserting a surgical hardware installation at a desired orientation through an insertion point of the bone by indicating when an orientation of the electronic device is within a threshold of the simulated orientation.

RELATED APPLICATIONS

This continuation application claims the benefit and priority ofpreviously filed provisional patent application U.S. App. No.62/145,686, filed Apr. 10, 2015 and titled “SYSTEM AND METHOD FORPEDICLE SCREW PLACEMENT IN VERTEBRA,” of previously filed provisionalpatent application U.S. Appl. No. 62/116,345, filed Feb. 13, 2015 andtitled “SYSTEM AND METHOD FOR PEDICLE SCREW PLACEMENT IN VERTEBRA,” andof previously filed nonprovisional patent application U.S. applicationSer. No. 15/043,480, filed Feb. 12, 2016 and titled “SYSTEM AND METHODFOR MEDICAL DEVICE PLACEMENT IN BONE,” and the contents of all arehereby incorporated by reference in their entirety.

TECHNICAL FIELD

This disclosure generally relates to medical systems. More specifically,this disclosure relates to an electronic device that generates outputwhich facilitates the aligning and orientation of surgical equipment foruse in inserting a medical device in a bone. In one implementation, thesurgical equipment is used to create a pilot hole in a vertebra forreceiving a pedicle screw at a precise orientation, such as a transverseangle, sagittal angle, or any other angle.

BACKGROUND

Patients who undergo certain procedures, such as a spinal fusion, mayhave pedicle screws placed into their vertebrae. The pedicle screws aretypically implanted into the vertebrae through the pedicles of thevertebrae. Once a pilot hole is created through the cortex of the bone,a probe is used to create the path through which the pedicle screw willbe placed into the vertebrae. Placing the pedicle screw at the correctangle helps to assure a mechanically sound construct and to avoid injuryto surrounding structures such as the spinal cord, nerve roots, andblood vessels. The orientation of the screw can be described in twoplanes: (1) the transverse plane, which is parallel to the ground if theperson is standing upright, and (2) the sagittal plane, which divides aperson into left and right halves.

To assist surgeons to properly place and orient a pedicle screw in avertebra, a variety of machines have been used. However, these machinesare typically costly and bulky, thereby reducing the number of availablesurgical suites that have suitable equipment for use in assisting asurgeon with properly placing and orienting a pedicle screw. Therefore,further developments in medical technology are needed so as to enablephysically smaller, cost effective devices that provide the desiredlevel of assistance to surgeons.

SUMMARY

This summary is provided to introduce a selection of concepts that arefurther described below in the detailed description. This summary is notintended to identify key or essential features of the claimed subjectmatter, nor is it intended to be used as an aid in limiting the scope ofthe claimed subject matter.

A method disclosed herein includes simulating an insertion point and anorientation of a simulated surgical hardware installation on adiagnostic representation of the bone, and then using an electronicdevice to align an instrument for inserting a surgical hardwareinstallation at a desired orientation through an insertion point of thebone by indicating when an orientation of the electronic device iswithin a threshold of the simulated orientation.

An apparatus disclosed herein is for determining orientation of aninstrument for inserting a medical device in a bone. The apparatusincludes an electronic device having an orientation sensor, and aprocessor. The processor is configured to simulate insertion of themedical device in an image of the bone to determine a desired insertionangle of the medical device relative to a plane of the bone, determinean orientation of the electronic device relative to the plane using theorientation sensor, and output a notification when the orientation ofthe electronic device is such that the electronic device is positionedadjacent the desired angle of the medical device relative to the plane.

Another method aspect is directed to a method for verifying an insertionangle of an instrument for determining a correct angle for a pediclescrew in a vertebra. The method includes aligning an axis of anapparatus with at least one of a sagittal plane, transverse plane, andcoronal plane of the vertebra in a representation thereof. The methodalso includes capturing an image of the representation of the vertebra,and generating an angle-indicative line on a display, wherein theangle-indicative line adjusts in response to rotation and orientation ofthe apparatus and provides a notification when the apparatus is at thecorrect angle, the correct angle being a desired angle between the axisof the apparatus and at least one of the sagittal plane, transverseplane, and coronal plane.

A further aspect is directed to a system for indicating an insertionsagittal angle of a tract for receiving a pedicle screw in a vertebra.The system includes an image acquisition unit, an orientation sensor, adisplay, and a processor. The processor is configured to obtain an imageof a cross sectional view in a transverse plane of the vertebra, usingthe image acquisition unit, and measure orientation of the system andcalibrate the orientation to align with a sagittal plane, transverseplane, or coronal plane of the vertebra. The processor is furtherconfigured to receive definitions of an insertion sagittal angle,transverse angle, or coronal angle of the tract and an initial positionthereof relative to the vertebra, and generate an angle-indicative lineon the display, wherein the angle-indicative line rotates in response torotation of the system, and provides a notification when at least aportion of the system approximately forms the insertion sagittal angle,transverse angle, or coronal angle between an axis of the apparatus andthe sagittal plane, transverse plane, or coronal plane of the vertebrae.

BRIEF DESCRIPTION OF THE DRAWINGS

For a more complete understanding of various embodiments of the presentinvention and the advantages thereof, reference is now made to thefollowing brief description, taken in connection with the accompanyingdrawings, appendices, and detailed description, wherein like referencenumerals represent like parts, and in which:

FIG. 1 illustrates definitions of a sagittal plane, a frontal plane, anda transverse plane relative to a patient's body;

FIG. 2A illustrates a cross-sectional view of a vertebra having pediclescrews installed in respective pilot holes;

FIG. 2B illustrates an example lateral view of a vertebra for installingpedicle screws;

FIG. 2C illustrates an example posterior view of a vertebra forinstalling pedicle screws;

FIG. 3A presents a schematic diagram of an apparatus used in accordancewith an embodiment to define and verify a sagittal angle for a pilothole;

FIG. 3B illustrates a schematic diagram for defining a sagittal anglefor a pilot hole in a vertebra;

FIG. 4A illustrates a schematic side view of a medical operation systemused in some embodiments for defining the sagittal angle of a vertebra;

FIG. 4B illustrates a schematic front view of a medical operation systemused in some embodiments for defining the sagittal angle of a vertebra;

FIG. 5A illustrates an example flow chart for a method of determining anorientation of an instrument for inserting a medical device in a bone,in accordance with one or more embodiments of the present disclosure;

FIGS. 5B, 5C, and 5D illustrate example flow charts for methods forindicating the sagittal angle, transverse angle, and coronal angle,respectively, in accordance with one or more embodiments of the presentdisclosure;

FIGS. 6A-6D illustrate example user interfaces for acomputer-implemented program to perform the methods shown in FIGS.5A-5D, wherein FIG. 6A illustrates an interface for selecting vertebraof a patient, FIG. 6B illustrates aligning the longitudinal axis of theapparatus with the sagittal plane, FIG. 6C illustrates defining apedicle screw's position and its sagittal angle, and FIG. 6D illustratesgenerating an angle-indicative line for showing the angle between thelongitudinal axis of the apparatus and the sagittal plane;

FIG. 7 illustrates an example application of the aligning methodpresented in FIG. 5B or 5C; and

Like elements are indicated with like reference numerals.

DETAILED DESCRIPTION

In the following detailed description and the attached drawings andappendices, numerous specific details are set forth to provide athorough understanding of the present disclosure. However, those skilledin the art will appreciate that the present disclosure may be practiced,in some instances, without such specific details. In other instances,well-known elements have been illustrated in schematic or block diagramform in order not to obscure the present disclosure in unnecessarydetail. Additionally, for the most part, specific details, and the like,have been omitted inasmuch as such details are not considered necessaryto obtain a complete understanding of the present disclosure, and areconsidered to be within the understanding of persons of ordinary skillin the relevant art.

It is further noted that, unless indicated otherwise, all functionsdescribed herein may be performed in hardware or as softwareinstructions for enabling a computer, radio or other device to performpredetermined operations, where the software instructions are embodiedon a computer readable storage medium, such as RAM, a hard drive, flashmemory or other type of computer readable storage medium known to aperson of ordinary skill in the art. In certain embodiments, thepredetermined operations of the computer, radio or other device areperformed by a processor such as a computer or an electronic dataprocessor in accordance with code such as computer program code,software, firmware, and, in some embodiments, integrated circuitry thatis coded to perform such functions. Furthermore, it should be understoodthat various operations described herein as being performed by a usermay be operations manually performed by the user, or may be automatedprocesses performed either with or without instruction provided by theuser.

This disclosure describes a system and computer-implemented method forindicating an angle formed between a guiding direction for drilling apilot hole (also referred to herein as a tract) for receiving a pediclescrew and a reference plane such as, for example, the sagittal plane.

The disclosed system and method may be implemented to guide theinsertion of pedicle screws at a desired angle. The desired angle may bea transverse angle, sagittal angle, or any other angle. This process mayinclude, in some embodiments, the creation of pilot holes.

FIG. 1 illustrates a sagittal or median plane 110, a coronal or frontalplane 120, and a transverse or horizontal plane 130 relative to apatient's body part 100 located at the intersection of the sagittalplane 110, coronal plane 120, and transverse plane 130. Each plane isorthogonal to each other. When discussing a vertebra (or other bodyparts) in the following disclosure, reference is made to the sagittalplane, coronal plane, and transverse plane. It should be understoodthat, when these planes are mentioned, they are not intended as areference to the specific sagittal, coronal, and transverse planesillustrated in FIG. 1, but rather, are intended as a reference toillustrate an orientation or location relative to the specific vertebrabeing discussed.

FIG. 2A illustrates a cross sectional view (i.e., superior view) 200 ofa vertebra 205 having pedicle screws 210 installed in respective pilotholes 220. A driver 230 may be used to screw the pedicle screws 210 intothe pilot holes 220. FIG. 2B illustrates a lateral view (i.e., sideview) 250 of a vertebra, and FIG. 2C illustrates a posterior view 270 ofa vertebra. The following discussion focuses on properly creating thepilot holes with a tool guided by the method disclosed.

FIG. 3A presents a schematic diagram of an apparatus 300 used to defineand verify an angle for a pilot hole, or tract, such as the pilot hole220 of FIG. 2. The apparatus 300 has an axis 305 (such as, for example,a longitudinal axis) that is used in some embodiments to align theapparatus 300 for image capture. The apparatus 300 includes an imageacquisition unit 320 for capturing an image 310 of the vertebra. In someembodiments, the image 310 may be obtained by positioning the apparatus300 and/or image acquisition unit 320 in parallel with the transverse,sagittal, or coronal plane to obtain an image of the vertebra.

In some embodiments, the image acquisition unit 320 can be a camerahaving sufficient field of view 360 to properly align the axis 305 ofthe apparatus 300 with the desired plane. In some embodiments, the axis305 is representative of a vertical line centered laterally with respectto the image being captured. For example, if the desired image isintended to capture the vertebra from a cross sectional, superior view(e.g., see FIG. 2A), the axis 305 is aligned with the sagittal plane(i.e., the plane that is sagittal to the vertebra) and the imageacquisition unit 320 is positioned parallel to the transverse plane tocapture the top-down view of the vertebra shown in FIG. 2A. If thedesired image is intended to capture the vertebra from a side view(e.g., a lateral image of the vertebra, see FIG. 2B), the axis 305 isaligned with the transverse plane (i.e., the plane that is transverse tothe vertebra) and the image acquisition unit 320 is positioned parallelto the sagittal plane. If the desired image is intended to capture thevertebra from a posterior or anterior view (see, for example, FIG. 2C),the axis 305 is aligned with the sagittal plane and the imageacquisition unit 320 is positioned parallel to the coronal plane.

In some embodiments, the image 310 may be a processed image, e.g., animage displayed on a screen, a film, or a printed photograph. In otherembodiments, the image acquisition unit 320 can directly use an imagetaken from an external machine (not illustrated), such as a radiograph,computed tomography (CT) scanner, or a magnetic resonance imaging (MRI)machine.

The orientation apparatus 330 is operable to detect changes in movement,orientation and position. In some embodiments, the orientation apparatus330 includes at least one of a gyroscope 332, an inertial measurementunit 334, and an accelerometer 336. The gyroscope 332 is operable tomeasure at least one axis of rotation, for example, the axis parallel tothe intersection of the sagittal plane and the coronal plane. In otherembodiments, the gyroscope 332 includes more than one sensing axes ofrotation, such as three axes of rotation, for detecting changes inorientation. The inertial measurement unit 334 can detect changes ofposition in one or more directions in a cardinal coordinate system. Theaccelerometer 336 can detect changes of speeds in one or more directionsin a cardinal coordinate system. In some embodiments, data from allcomponents of the orientation apparatus 330 are used to calculate thecontinuous, dynamic changes in orientation and position.

The apparatus 300 further includes, in some embodiments, an inputcomponent 340 that is operable to receive user input, and insertionlocation and the desired angle representing an insertion direction ofthe pedicle screw. An example illustration of the user input component340 is presented in accordance with FIGS. 6A-6D. In some embodiments,the input component 340 can include a multi-touch screen, a computermouse, a keyboard, a touch sensitive pad, or any other input device.

In some embodiments, the apparatus 300 further includes a processor 350.The processor 350 can be any processing unit capable of basiccomputation and capable of executing a program, software, firmware, orany application commonly known in the art of computer science. As to beexplained, the processor 350 is operable to output an angle-indicativeline representing the apparatus orientation on the display. In someembodiments, the angle-indicative line provides a notation that theorientation of the apparatus 300 approximately forms the desired angle.The angle-indicative line is not limited to showing sagittal angles, butalso angles in different planes, such as, for example, the coronal planeor the transverse plane.

The apparatus 300 may, in some embodiments, further include a memorystorage unit 352 and network module 354. The memory storage unit 352 canbe a hard drive, random access memory, solid-state memory, flash memory,or any other storage device. Memory storage unit 352 saves data relatedto at least an operating system, application, and patient profiles. Thenetwork module 354 allows the apparatus 300 to communicate with externalequipment as well as communication networks.

In some embodiments, the apparatus 300 further includes a display 360.In some embodiments, the display 360 is a liquid crystal display for amulti-touch screen. In some embodiments, the display 360 shows theangle-indicative line to a user and provides a notification when theapparatus is approximately aligned with the predefined desired angle.For example, the notification can include a highlighted line thatnotifies the user the axis 305 has reached the desired angle, or iswithin an acceptable range of the desired angle.

Referring briefly to FIG. 7, in some implementations, the apparatus 300further includes an attachment support or mechanism that allows theapparatus 300 to be attached to medical equipment, for example, forcreating the pilot holes as shown in FIG. 7. The attachment mechanism700 may be comprised of plastic, stainless steel, titanium, or any othermaterial. The attachment mechanism 700 couples the apparatus 300 to theequipment 702 by, for example, providing a casing that is attached tothe apparatus 701 and is configured to connect to the equipment 702. Insome embodiments, the attachment mechanism 700 may include a magneticattachment apparatus for coupling the apparatus 300 to the equipment702. The attachment mechanism 700 allows the apparatus 300 to providereal-time measurement and display of the orientation of the attachedmedical equipment 702.

FIG. 3B illustrates a schematic diagram for defining the sagittal angle370 for the pilot hole 220 in the vertebra 205. The field of view 360 ofthe image acquisition unit 320 allows a user to align the axis 305 ofthe apparatus 300 with the desired plane (e.g., the sagittal plane). Inthe embodiment shown in FIG. 3B, the sagittal angle 370 is the anglebetween the central axis 365 of the pilot hole 220 and the sagittalplane.

FIG. 4A illustrates a schematic side view of a medical operation system400, which may be used in some embodiments for defining the sagittalangle 370 of the vertebra shown in FIGS. 3A and 3B. The medicaloperation system 400 includes a machine 410 for capturing across-sectional view of the vertebra 205. The machine 410 may be, forexample, a CT scanner or MRI machine. The patient 108 exits the machine410 after the image is taken, as shown in FIG. 4B.

FIG. 4B illustrates a schematic front view 450 of the medical operationsystem 400 taken in the transverse plane for defining the sagittal angle370 of the vertebra 205. The axis of the pilot hole 460 should to beprecisely defined for the drilling guide 455. In some embodiments, theapparatus 300 may be attached to the drilling guide 450 with theattachment mechanism 308. Defining and verifying the sagittal angle 370may be performed at the apparatus 300, as explained in connection withthe method illustrated in FIG. 5B.

First, however, a method of determining an orientation of an instrumentfor inserting a medical device in a bone is now described with referenceto the flowchart 501 of FIG. 5A.

First an insertion point and an orientation of a simulated surgicalhardware installation are simulated on a diagnostic representation of abone 502. Then, an electronic device is used to align an instrument forinserting a surgical hardware installation at a desired orientationthrough an insertion point of the bone by indicating when an orientationof the electronic device is within a threshold of the simulatedorientation 503.

Simulating the insertion point and the orientation of the simulatedsurgical hardware installation on the diagnostic representation of thebone includes acquiring the diagnostic representation of the bone 504,aligning the diagnostic representation of the bone with a referencepoint 505, designating the insertion point of the simulated surgicalhardware installation on the diagnostic representation of the bone 506,and designating the orientation of the simulated surgical hardwareinstallation on the diagnostic representation of the bone relative tothe reference point 507.

Using the electronic device to align the instrument for inserting thesurgical hardware installation at the desired orientation through theinsertion point includes aligning the electronic device with theinstrument at the insertion point 508, tracking movement of theelectronic device and the instrument using an orientation sensor of theelectronic device until the orientation of the electronic device and theinstrument are within the threshold of the simulated orientation 509,and indicating when the electronic device and the instrument are withinthe threshold of the simulated orientation 511.

FIG. 5B illustrates an example flow chart 500 of a method for indicatingthe sagittal angle 370. The method of the flowchart 500 is for verifyingany insertion angle 370 of the pilot hole 220 in the sagittal plane 110for receiving a pedicle screw 210 in the vertebra 205. At 510, the axis305 of the apparatus 300 is aligned with the sagittal plane. In someembodiments, a user may hold the apparatus 300 and rotate the apparatus300 to match a marking indicating the axis 305 with features of thevertebra 205 that indicate the sagittal plane. In some embodiments, themarking may be displayed on the screen as the user aligns the device.

At 520, the image of the cross-sectional view is captured in thetransverse plane. In one embodiment, the apparatus 300 includes a smartphone, a tablet computer, a laptop computer, or any portablecomputational device including those that include a camera for capturinga representation of the cross-sectional view of the vertebra 205. Inother embodiments, the image of the vertebra 205 may be sent to theapparatus 300 via a wired or wireless connection to be displayed on theapparatus 300 such that no physical representation (e.g., films, photos,monitors) may be needed for this step.

At 530, definitions of the insertion sagittal angle 370 of the pilothole 220 and the initial position 375 of the pilot hole are provided bya user. This input operation may be performed using various inputdevices, including a computer mouse, a keyboard, a touchscreen, or thelike. In one embodiment, a multi-touch screen (e.g., the display 360) isused for both displaying the image and receiving the definition inputfrom a user. Example illustrations of this input are provided in FIGS.6A-6D.

At 540, an angle-indicative line is generated by a processor anddisplayed on the display 360. The angle-indicative line can rotate inresponse to the apparatus 300 rotation and provides a notification whenthe apparatus 300 approximately forms the insertion sagittal angle 370between the apparatus 300 longitudinal axis 305 and the sagittal plane.In some implementations, the angle-indicative line is a rotating linegenerated in the display 360 that allows a user to constantly monitorthe change of orientation of the apparatus 300. The orientationmonitoring is performed with an orientation apparatus 330. Morespecifically, in some embodiments, a gyroscope 332 that includes atleast one axis of rotation may provide the function of monitoring theapparatus's orientation or position.

The indicative line may generate notations in various forms, including avisual alert such as highlighting the angle-indicative line, an audioalert such as providing a continuous sound with variable frequencyindicative of the proximity between the current angle and the desiredangle, and a small vibration that allows the user to notice the angularchange. It should be appreciated that any audio alert may be used, suchas a single sound or series of sounds when the desired angle is reached.Likewise, a single vibration or a series of vibrations may be emittedwhen the desired angle is reached. In some implementations, the flowchart 500 illustrated in FIG. 5B may be applicable for generatingindication angles in the transverse plane or the coronal plane forindicating a respective transverse angle or a coronal angle.

FIG. 5C illustrates a flow chart 550 of an implementation for indicatinga transverse angle, which is an angle with respect to the transverseplane of the vertebra. The method of the flowchart 550 is for verifyingany pedicle screw insertion angle in the transverse plane of thevertebra 205. At 560, the axis 305 of the apparatus 300 is aligned withthe transverse plane. In some embodiments, a user may hold the apparatus300 and rotate the apparatus 300 to match a marking indicating the axis305 with features of the vertebra 205 that indicate the transverseplane. In some embodiments, the marking may be displayed on the screenas the user aligns the device.

At 570, the image of the posterior view is captured in the coronalplane. In one embodiment, the apparatus 300 includes a smart phone, atablet computer, a laptop computer, or any portable computational deviceincluding those that include a camera for capturing a representation ofthe cross-sectional view of the vertebra 205. In other embodiments, theimage of the vertebra 205 may be sent to the apparatus 300 via a wiredor wireless connection to be displayed on the apparatus 300 such that nophysical representation (e.g., films, photos, monitors) may be neededfor this step.

At 580, definitions of the insertion angle in the transverse plane 130,and the initial position 375 of the pilot hole are provided by a user,as similar to the sagittal angle defined at 530.

At 590, an angle-indicative line for the corresponding transverse angleis generated by a processor and displayed on the display 360. Theangle-indicative line can rotate in response to the apparatus 300rotation and provides a notification when the apparatus 300approximately forms the insertion transverse angle, as defined in step580, between the apparatus 300 longitudinal axis 305 and the transverseplane. In some implementations, the angle-indicative line is a rotatingline generated in the display 360 that allows a user to constantlymonitor the change of orientation of the apparatus 300. The orientationmonitoring is performed with an orientation apparatus 330. Morespecifically, in some embodiments, a gyroscope 332 that includes atleast one axis of rotation may provide the function of monitoring theapparatus's orientation or position.

FIG. 5D illustrates a flow chart 555 of another implementation forindicating a coronal angle. The method of the flowchart 555 is forverifying any insertion angle of a pedicle screw 210 in the vertebra 205in the coronal plane 120. At 565, the axis 305 of the apparatus 300 isaligned with the coronal plane. In some embodiments, a user may hold theapparatus 300 and rotate the apparatus 300 to match a marking indicatingthe axis 305 with features of the vertebra 205 that indicate the coronalplane. In some embodiments, the marking may be displayed on the screenas the user aligns the device.

At 575, the image of the lateral view is captured in the sagittal plane.In one embodiment, the apparatus 300 includes a smart phone, a tabletcomputer, a laptop computer, or any portable computational deviceincluding those that include a camera for capturing a representation ofthe posterior view of the vertebra 205. In other embodiments, the imageof the vertebra 205 may be sent to the apparatus 300 via a wired orwireless connection to be displayed on the apparatus 300 such that nophysical representation (e.g., films, photos, monitors) may be neededfor this step.

At 585, respective definitions of the insertion angle in the coronalplane 120, and the initial position 375 of the pilot hole are providedby a user, as similar to the sagittal angle defined at 530.

At 595, an angle-indicative line for one of the corresponding coronalangle is generated by a processor and displayed on the display 360. Theangle-indicative line can rotate in response to the apparatus 300rotation and provides a notification when the apparatus 300approximately forms the insertion coronal angle between the apparatus300 longitudinal axis 305 and the coronal plane. In someimplementations, the angle-indicative line is a rotating line generatedin the display 360 that allows a user to constantly monitor the changeof orientation of the apparatus 300. The orientation monitoring isperformed with an orientation apparatus 330. More specifically, in someembodiments, a gyroscope 332 that includes at least one axis of rotationmay provide the function of monitoring the apparatus's orientation orposition.

FIGS. 6A-6D illustrate examples of user interfaces for controlling acomputer implemented program to perform the methods shown in FIG. 5A-5D.FIG. 6A illustrates an interface 600 for selecting vertebra of apatient, FIG. 6B illustrates aligning the axis 305 of the apparatus 300with the sagittal plane, FIG. 6C illustrates defining a pedicle screw'sposition and its sagittal angle 370, and FIG. 6D illustrates generatingan angle-indicative line 652 for showing the angle between thelongitudinal axis of the apparatus and the sagittal plane. In someembodiments, the angle-indicative line may represent a virtual gearshiftprobe, or other instrument for aligning a pedicle screw or pilot hole.Where the virtual gearshift is properly aligned, the virtual gearshiftmay change colors, or may change length or width. The angle-indicativeline can rotate in response to the apparatus 300 rotation and provides anotification when the apparatus 300 approximately forms the insertioncoronal angle between the apparatus 300 longitudinal axis 305 and thecoronal plane.

In FIG. 6A, the patient's profile may be selected or added by typing thelast name of the patient in the window 610. The corresponding vertebrafor the desired angle is selected in the window 620. The camera button640 allows a user to take a picture of the vertebra. The picture is thenshown in the window 630. The button 650 allows the user to move onto thenext step. As previously discussed, the picture at the vertebra may beprovided without use of the camera or camera button 640.

For example, by using a camera of a mobile device, a user can take apicture of an axial view (either CT or MRI) in the transverse plane 130,of the desired vertebral body 205. Use the red line 622 to line up thevertebral body so that it is proximately vertical for aligning with thesagittal plane (or other desired plane), as shown in FIG. 6B. A retakebutton 624 allows the user to go back to the previous steps to retakethe image to ensure the alignment is proper. The button 626 allows theuser to select the current photo to be used in the following operations.

After selecting button 626, the user may be returned to the detail viewas shown in FIG. 6C. The photo may, in some embodiments, beautomatically flipped to approximate its position during surgery. Button642 may be selected to flip the orientation of the photo. For example,the RL button 642 can be used to flip the picture (and pedicle screw)depending on whether the surgeon is placing the screw while lookingtowards the patient's head or towards their feet.

The user next selects the optimal pedicle screw position by selectingthe navigation button 644 and by moving the crosshairs 633 to thecortical entry point of the screw, then tapping the trajectory button634 and rotate the screw to its desired position 635.

Tap the Nav button 644 and a virtual gearshift probe 652 appears on thescreen. The gearshift probe's orientation matches the orientation of theapparatus 300. In some embodiments, once the angle of the gearshiftprobe 652 is about 20 degrees within the selected trajectory, thegearshift probe 652 will turn yellow, at 5 degrees, it will turn green,and when the alignment is within 1 degree of the target angle, a greenline 654 will extend outward and the pedicle screw will disappear.

In some embodiments, the device or apparatus 300 can be placed in asterile bag and then be placed against the gearshift probe as it isbeing used to create the path for the pedicle screw.

Some gearshift probes may be too short to allow the device (apparatus300) to be placed against them lengthwise. If this is the case, tap the90 degree button 656 and the screen will be rotated so the short edge ofthe device can be placed against the gearshift probe.

Other implementations of the disclosed system and method are possible.For example, the apparatus 300 may also use a second or more views todefine various angles not limited within the sagittal plane. For exampleand in accordance with the foregoing disclosure, images may be capturedfrom the superior, lateral, posterior, anterior views, and variouscombinations thereof, to provide multiple reference points so thatthree-dimensional representations of the alignment angles can bepresented.

In addition, different mobile computer devices may be used or modifiedinto the apparatus 300 by equipping corresponding image acquisitionunits, input terminals, and motion or orientation sensing units. In someembodiments, the apparatus 300 includes a smart phone or anotherelectronic device having a gyroscope. In addition, other motion ororientation sensors may be included such as the inertial measurementunit 334, and the accelerometers 336. The apparatus 300 may also beattached onto various medical devices or equipment for guiding insertionangles that require high precision and ease of use. The smartphone maybe an iPhone for example. Also, in some application, the mobile computerdevice may be an iPod Touch, iPad, Android phone, Android tablet,Windows Phone, Windows tablet, or Blackberry phone. Also, in someapplications, the mobile computer device may be an Apple TV incombination with an Apple TV remote, or a Nintendo Wii in combinationwith a Nintendo Wii remote. Indeed, the mobile computer device may beany combination of electronic devices where the orientation sensor (suchas a gyroscope) is in one electronic device and the processor is inanother electronic device.

In some embodiments, axis other than the device's longitudinal axis maybe used. Axes can be defined by a portion of the device (e.g., an edgeor surface of the device). More than one orientation apparatus 330 maybe used at the same time to give a three-dimensional viewing. Surgicalapparatus may include pedicle screws, gearshift probes, and othermedical devices.

Although the preceding description has been described herein withreference to particular means, materials and embodiments, it is notintended to be limited to the particulars disclosed herein; rather, itextends to all functionally equivalent structures, methods, and uses,such as are within the scope of the appended claims.

What is claimed is:
 1. A method for determining orientation of aninstrument for placing a medical device in a bone, comprising:simulating an insertion point and simulating an orientation of asimulated medical device on a diagnostic representation of the bone; andusing an electronic device to align the instrument for placing themedical device, according to the simulation of the simulated medicaldevice, at a desired orientation through an insertion point of the boneby indicating when an orientation of the electronic device is within athreshold of the simulated orientation.
 2. The method of claim 1,wherein simulating the insertion point and the orientation of thesimulated medical device placement on the diagnostic representation ofthe bone comprises: acquiring the diagnostic representation of the bone;displaying the diagnostic representation of the bone on the electronicdevice; aligning the diagnostic representation of the bone with areference point; designating the insertion point of the simulatedmedical device on the diagnostic representation of the bone; designatingthe orientation of the simulated medical device on the diagnosticrepresentation of the bone relative to the reference point.
 3. Themethod of claim 1, wherein using the electronic device to align theinstrument for placing the medical device at the desired orientationthrough the insertion point comprises: aligning the electronic devicewith the instrument at the insertion point; tracking a position of theelectronic device and the instrument using an orientation sensor of theelectronic device until the orientation of the electronic device and theinstrument are within the threshold of the simulated orientation;indicating when the electronic device and the instrument are within thethreshold of the simulated orientation.
 4. The method of claim 3,wherein indicating when the electronic device and the instrument arewithin the threshold of the simulated orientation comprises comparing afirst graphical element representing the orientation of the electronicdevice and a second graphical element representing the desiredorientation through the desired insertion point of the medical device.5. The method of claim 1, wherein the desired orientation is a desiredangle between the electronic device and a plane of the bone representedin the diagnostic representation of the bone.
 6. The method of claim 1,wherein the diagnostic image is an axial CT scan of the bone.
 7. Amethod for verifying an insertion angle of an instrument for determininga correct angle for a pedicle screw in a vertebra comprising: aligningan axis of an apparatus with at least one of a sagittal plane,transverse plane, and coronal plane of the vertebra in a representationthereof; capturing an image of the representation of the vertebra;generating an angle-indicative line on a display, wherein theangle-indicative line adjusts in response to rotation and orientation ofthe apparatus and provides a notification when the apparatus is at thecorrect angle, the correct angle being a desired angle between the axisof the apparatus and at least one of the sagittal plane, transverseplane, and coronal plane.
 8. The method of claim 7, wherein aligning theaxis of the apparatus further comprises monitoring the axis on thedisplay when the apparatus rotates in the transverse plane.
 9. Themethod of claim 7, wherein aligning the axis of the apparatus furthercomprises initializing an orientation sensor of the apparatus when theaxis is aligned with the sagittal plane.
 10. The method of claim 7,wherein generating the angle-indicative line further comprises:originating the angle-indicative line at a position of a receiving hole;and synchronizing rotation of the angle-indicative line with therotation of the apparatus.
 11. The method of claim 7, wherein capturingan image of the representation of the vertebra comprises displaying adiagnostic representation of the vertebra on the display generating theangle-indicative line.
 12. The method of claim 11, wherein generatingthe angle-indicative line on the display further comprises displaying afirst graphical element representing the orientation of the apparatusand a second graphical element representing the desired insertion angleof the apparatus.
 13. An apparatus for determining orientation of aninstrument for placing a medical device in a bone, the apparatuscomprising: an electronic device configured to display a representationof the bone, the electronic device comprising: an orientation sensor; aprocessor configured to: simulate a positioning of the medical devicewith an image of the bone to determine a desired insertion angle of themedical device relative to a plane of the bone; determine an orientationof the electronic device relative to the plane of the bone using theorientation sensor; output a notification when the orientation of theelectronic device is such that the electronic device is positioned at orabout the desired insertion angle of the medical device relative to theplane of the bone, wherein the notification includes at least a firstgraphical element that corresponds to the orientation of the electronicdevice relative to the plane of the bone.
 14. The apparatus of claim 13,wherein the processor is further configured to use an additional imageof the bone to determine when the electronic device is positioned at orabout an additional desired insertion angle with an additional plane ofthe bone, and to output an additional notification when the electronicdevice is positioned at or about the additional desired insertion angle.15. The apparatus of claim 13, wherein the image of the bone is asuperior view of the bone, a lateral view of the bone, or a posteriorview of the bone.
 16. The apparatus of claim 13, wherein the image ofthe bone is a pictorial view of the bone, an x-ray of the bone, aradiograph of the bone, a computed tomography scan of the bone, or amagnetic resonance image of the bone.
 17. The apparatus of claim 13,wherein the plane is a transverse plane, coronal plane, or a sagittalplane.
 18. The apparatus of claim 13, wherein the processor is furtherconfigured to determine the orientation of the electronic device bydetermining an orientation of a longitudinal axis of the electronicdevice.
 19. The apparatus of claim 13, wherein the medical devicecomprises a screw or a probe.
 20. The apparatus of claim 13, furthercomprising an attachment mechanism configured to affix the electronicdevice to the instrument for creating an opening in the bone forreceiving the medical device.
 21. The apparatus of claim 13, wherein theorientation sensor comprises at least one of a gyroscope, anaccelerometer, and an inertial measurement unit.